Free Readability Checker
Paste your text to see how easy it is to read — reading ease, grade level, multiple indices, and the hardest sentences to fix. Runs in your browser.
What is a readability checker?
A readability checker measures how hard your text is to read. It counts words, sentences, and syllables, then turns them into scores — the Flesch reading ease score and several grade-level indices — and points out the sentences most in need of work.
This checker runs entirely in your browser. Paste or type your text and the scores, stats, and hardest sentences update instantly. Nothing you write is uploaded.
How to check readability
Paste your text
Drop in a paragraph, an article, or a whole page of copy.
Read the scores
Check the reading ease, the grade levels, and which sentences are hardest.
Fix and re-check
Rewrite the flagged sentences, then watch the scores improve.
What this tool offers
Flesch reading ease
The 0-100 score with a plain-language rating.
Multiple indices
Flesch-Kincaid, Gunning Fog, and SMOG grade levels.
Hardest sentences
The longest, densest sentences flagged to fix first.
Word stats
Words, sentences, and average sentence length.
Live updates
Every number recalculates as you edit.
100% in your browser
Your text is never uploaded or stored.
Why does readability matter?
On the web, most people skim. Dense, complex writing makes them work, and working readers leave. Clear, simple text keeps visitors on the page, helps them act, and is easier for everyone — including non-native speakers and people reading on a phone.
Readability also helps search. Search engines favour content people actually read and stay with, and a readable page earns more time-on-page and fewer bounces. Aiming for a reading ease around 60 or higher — roughly an 8th-grade level — suits most websites well.
The Flesch reading ease scale
What the score means and who can read it comfortably.
| Score | Rating | Reading level |
|---|---|---|
| 90-100 | Very easy | 5th grade |
| 70-89 | Easy to fairly easy | 6th-7th grade |
| 60-69 | Standard | 8th-9th grade |
| 50-59 | Fairly difficult | 10th-12th grade |
| 30-49 | Difficult | College |
| 0-29 | Very difficult | College graduate |
Frequently asked questions
What is a good readability score?
For most websites, aim for a Flesch reading ease of about 60 or higher — roughly an 8th-grade level. Marketing and general content read best at 60-70; technical or academic writing naturally scores lower.
What are the different indices?
Flesch-Kincaid, Gunning Fog, and SMOG each estimate the school grade needed to read the text, using slightly different formulas. When they roughly agree, you can trust the result; a wide spread usually means unusual vocabulary or sentence structure.
How do I make my text more readable?
Start with the hardest sentences this tool flags. Break each long one in two, swap long words for short ones, cut filler, and use active voice. Re-check after each change — the scores respond immediately.
How accurate is the syllable count?
Syllables are estimated with a standard rule-based method, which is accurate for most English words. A few unusual words may be off by one, but the overall scores stay reliable.
Is my text private?
Yes. The text is analysed entirely in your browser. Nothing you paste is uploaded, stored, or sent to a server.
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